Hi!
We had the same situation couple of months ago when our baby was 6 months old and we were in a day 65 lessons. The stage lasted for 5 weeks and my guess is it was because our baby was not ready to understand the concept of "addition". He was still interested of quantities but lost interest otherwise. We have since then done one lesson every now and then, skipped Sessions 2 for each day and today was the first day we did entire Session 1 without a break since more than a month.
I think it is good thing to have a break and wait until the baby catches the interest again. I think the LM software is great because I would hate to make Doman quantities flash cards manually or with PowerPoint but there are couple of things that could ease small babies enjoying the software more.
One thing is that especially addition sessions are far too long. They should be max 5-6 equations long to be exciting for an infant. Current lesson length makes it also hard to cut the session immediately when you get the feeling the baby has seen enough because you wouldn't want to rewatch or miss any content if not required. One thing which would make equation sessions more fun would be to change the icon during the lesson (this could be also made by dividing the content to sessions of fewer equations and having a icon for each).
Also some Smilies icons and yellow flower icon (icon-flower-daffodil.gif) are not bright enough to be interesting as a small icons (maybe just drop pink, white, light purple and light yellow icons).
One thing is also the picture editor which could be a bit easier as I was unable to find how to change the icon background to be invisible.
Thank you of the great software!